For some reason using my DHT22 sensor I keep getting "NaN". I have tried using older versions of the DHT22 sensor library as suggested by a few of my searches, but it still doesn't fix the issue.

Also I can't get it to work with the GET request portion. Any help would be greatly appreciated.

#include <Adafruit_Sensor.h>
#include <DHT.h>
#include <ESP8266WiFi.h>
#include <Phant.h>
#include <ESP.h>

#define DHTPIN 2
#define DHTTYPE DHT22

const char* ssid = "Myyyyyyh";
const char* password = "Ixxxxx1";
const char* host = "script.google.com";

//*****example address
const String gardenchart = "/macros/s/AKfycbyNnWoTzK6/exec?";
const byte sleeptime = 1;
const byte NUM_FIELDS = 5;
const String fieldNames[NUM_FIELDS] = {"ghumidity", "gtemp", "light", "otemp", "wtemp"};
String fieldData[NUM_FIELDS];

void setup() {
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
  fieldData[0] = 1;
  ESP.deepSleep(sleeptime * 60 * 1000000, WAKE_RF_DEFAULT);

void loop() {

void postdata() {
  fieldData[0] = dht.readHumidity();
  fieldData[1] = dht.readTemperature(true);
  WiFiClient client;
  const int httpPort = 80;
  if (!client.connect (host, httpPort)) {
  for (int i=0; i<NUM_FIELDS; i++) {
    client.print("GET ");
    client.print(fieldNames[i]); client.print("&value=");
    client.print(fieldData[i]); client.print(" HTTP/1.1");
    client.println("Host:"); client.print(host);
    Serial.print(fieldNames[i] + fieldData[i]); delay(500);
  client.println("Connection: close");

The Adafruit DHT library causes a shortcut on the signal line. That can be a problem for Arduino boards, but it is a big problem for the ESP8266.
Issue: DHT init sequence wrong #48
I don't know what is a bigger problem, the shortcut in the code or Adafruit not fixing it.

Why do you mention the Arduino Uno with a label ?
For the "GET" you should find a good working example.

The DHT22 is not very good. There are better sensors with a normal I2C interface, for example the HTU21D-F or the BME-280. This is about a great test: Hackaday: Humidity Sensor Shootout. The BME-280 is the undisputed winner.

  • I'll look for a BMW, for the GET request it was working when I was using sparkfun's data hosting. I am switching to posting to my Google sheet and that's when something isn't working quite right. May 28 '17 at 12:26

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